Process of producing finely-divided carbon



R. W. POINDEXTER.

PROCESS OF PRODUCING FINELY DIVIDED CARBON'.

APPLICATON FILED JAN. 5.1920.

Patent-ed Jan. 10, 1922.

2 SHEETS-SHEET 5.

R. W POIHDEXTER. PROCESS 0F PRODUCING FINELY DIVDED CARBON.

APPLICATON FILED JAN. 6.1920.

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ROBERT WADE IPOKNDEXTm, 0F LOS ANGELES, CALIFOIA, ASSGNOR T0 NDIS GOUD/WIN, 0F LOS ANGELESQCA'LIFRNIA.

PROGSS'VOF PRODUCING FINELY-DIVIDED CBON.

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Specification of Letters Patent.

Patentes aan. iaiaaa.

Application ledlanuary 6, 1920. Serial No. 349,830.

.purposes must be produced in an extremely finely divided state and must be free from tars or other binding materials which tend to impair its color and render it otherwlse 'unsuitable for certain industrial purposes notably in connection with the manufacture and treatment of rubber.

The principal object of my invention is to provide a process and apparatus by which carbon may be produced in high yield quantity at a low cost and in an extremely finely divided condition reasonably free from tars, oils or other deleterious substances.

A further object of my invention is to provide a' process that will be highly efficient and economical.

Further objects and advantages will be set forth more in detail hereinafter.

Referring to the drawings which are for illustrative purposes only.

Fig. 1 is a side elevation partly in section on a plane represented by the line 1-1 .of

2. if ig. 2 is a plan view partly in section' on 'a plane'VA represented by the line 2-'2 of Fig. p

Fig. 3 is a' section on a plane represented by the line 3-3 of Fig. 2.

Fig. 4 is a section on a plane represented by the Vline 4--4 of Fig. 2.

The'apparatus illustrated in these drawing consists'primarily of a gas heated chamber 11,' a mixing chamber 12, a reaction 'chamber 13, a collection chamber'14 and two flair heatin stoves 15 and 16. Many difu A'fferenthy rocarbons may be used for the -production yof finely divided carbon, but l lifv'found that natural lgas furnishes a cheap" and# satisfactory source of supply. Tliis'gas is'supplied to a pipe 20, controlled by a valve' 21 and also to a pipe 22 controlled by a valve 23. The gas fromthe pipe 2 0 is carried through a heating coil l25j consisting of vertical pipes joined at the top and bottom to form a continuous coil located in the heating chamber 11. The ed in this coil as will hereina ter be'explained being delivered through an opening as is heat- 26 vinto a passage 27 which is separated from the mixing chamber 12 by a checker work 28 of iire br1ck. This checker work provides a multiplicity of narrow slots or openings through which the hotr gas'is forced in a large number of jets. rlihe gas heating chamber 11 is heated primarily by means of gas supplied through the pipe 22 to a pipe 30 which is controlled by a valve 31', gas eing forced into the chamber 1l where it is ignited, the products 0f combustion escaping through an opening 32 at the top gases is delivered into the mixing chamber 12 from'a passage'40 through a checker work 41v which is lsimilar in constructionto the checker work 28. The passage 40 is supthereof. Airor another gas or mixture of V plied through a throat 42 from one of the stoves 15 or 16, valves 43 and 44 being provided to shut oif the throat 42 from either- -of these stoves.

The sto'ves 15 and 16-consist of towers whichare filled with a Vbrick s oV checker work 45 and which f are provided With an opening 46 in the extreme top thereof. The stoves are heated initially by natural gas supplied through the pipe 22,l through valves 47 and 48 air being admitted through pipes having dampers v49 and 50. lIn starting the apparatus natural gas is ad.- mitted to the bottom o-f the stoves together with combustion air, this gas being burned in the stoves and thereby heating the checker work 4.5 which will store up the heat for considerable periods. Two stoves 15 and 16 are provided so that one of them may be heated while air is being heated in the other. If it is desired to heat the stove 15,

for example, the valve 43 is` closed, the valve 47 is opened, and a damper 49 is opened allowing combustion to take placel in the stove andhheating up thechecker work 45. The.

stove 16 may of course be heated by closing the valve 44 and opening the valve 48 and the dampery 50. An exhaust fan 6 0 is provided for' the purpose of forming a partial vacuum in the collection chamber 14, this vacuum tending to pull gas into the gas manifold 27 and to pull a-lr inthe' air pas-v sage 40. The stove 16 having been previf ously heated, for example, the valve 44 is opened and lair is pulled in through the opening 46 in the top of the stove 16 passing through the checker Work in which 1t 1s highly heated and passing through the throat 42 into-the passage 40; this air passes in a series of tiny jets through the checker Work 41, these jets mixing With the j ets of gas from the gas manifold 27. The mixture of air and gas passes from the mixing chamber 12 into the reaction chamber 13 and a partial combustion of the natural gas may take.place in the reaction chamber 13 with the result that hydrogen is liberated and finely divided free carbon is formed'. This free carbon is deposited on a series of plates 61 and as these deposits increase the carbon falls into the bottom of lthe collection chamber 14 being removed therefrom by means of a screw conveyor 63v driven from any suitable source. A mixed gas comprising hydrogen, together with carbon monoxideand some carbon dioxide, is drawn off Athrough the exhaust fan 60 and after the apparatus is once started this mixed gas 1s fed through the pipe into the gas heatmg chamber 11 where it' is burned to supplythe necessary pre-heating to the asin the pipes 25. The mixed gas is also ed through the yso valves 47 and 48 into one of the stoves 15 or .16 for the purpose of heating the brick checker Work. When the apparatus is operating properly no'gas is supplied to the pipe 22, the valve 23 being` closed, the necessary heat-for combustion being supplied by the mixed gases withdrawn from the chamber 14 by the exhaust 60. l

In practice I find it is desirable to heat the gas in the. coils 25 to apoint justlbelow the decomposition temperature, which in practice may be' 800 to 1100 C., the gas passing through the checker work 28 is therefore at a temperature just below its decomposition temperature and very little heat need be supplied to decompose and produce the 'carbon black.l The necessary heat for decomposition when operated in' this manner is furnished by the highly heatedair delivered from the stoves 15 or 16; this, air may be very much higher in temperature than the decomposition temperature of the natural gas in which case a very small volume need be supplied to break the gas up. This'breaking up is partially'accomplished when air is used by the combustion of a portion of the natural gas 'but the greater portion is broken up by the high temperature of the air, in fact I have found that non-oxidizing gases may be used in the stoves 15 and 16 with perfect success, it being, however, more convenient to use air.

claim as my invention 1. A process of producing a finely divided carbon which comprises heating a hydrocarbon to a degree slightly less than its decomposition temperature; mixing said hypartial combustion takes place so that a portion of `the hydrocarbon is broken up to form free carbon; and thereafter collecting said free carbon.

3. A process of producing a finely divided carbon Which comprises heating a hydrocarbon to a degree slightly less than its decomposition temperature; mixing said hydrocarbon with heated air in such al manner that a partial combustion takes place so that a portion of the hydrocarbon is broken up to form free carbon; and thereafter collecting said free carbon.

4. A process of producing a finely divided carbon Which comprises heating a hydrocarbon to a degree slightly less than its decomposition temperature; mixing said hy. drocarbon With ai heated above said decomposition temperature so that a portion of the hydrocarbon is broken up to form free carbon; and thereafter collecting said free carbon.

5. A process of producing a finely divided `'carbon which comprises heating a gas containing hydrocarbons to a degree slightly less than the decomposition temperature of the hydrocarbons; mixing said gas With a gas heated above said decomposition temperature so that a portion of the hydrocarbon is broken up to form free carbon; and thereafter collecting said free carbon.

6. A process of producing a finely divided carbon Which comprises heating a gas containing hydrocarbons to a degree slightly less than the decomposition temperature of the hydrocarbons; mixing said gas with air in'such a manner that a partial combustion takes place so that a portion of the hydrocarbon is broken up to form free carbon; and thereafter collecting said free carbon.

7. A process of producing a finely divided carbon which comprises heating a gas containing hydrocarbons to a degree slightly less than the decomposition temperature of the hydrocarbons; mixing said gas Wlithheatedair in such a manner that a partial combustion takes place so that a portion of the hydrocarbonis broken up to form free carbon; and thereafter collecting said free carbon.

8. A processof producing a finely divided carbon which comprises heating a gas conthe hydrocarbons; mixing said gas with air 'heated above said decomposition temperature so that'a portion of the hydrocarbon is 10. A process of producing a finely divided carbon which comprises heating air in quantities insuflcient to support complete combustion to a point near the deeompositionl temperature of a hydrocarbon;y mixing said hydrocarbon with saidy heated air so that a portion of said hydrocarbon is brok-en up to form free carbon; and thereaftercollecting 20 said free carbon. A

In testimony whereof, I have hereunto Iset my hand at Los Angeles, California, this 30th day of December, 1919.

ROBERT WADE POINDEXTER. 

